1. Field of the Invention
The present invention relates generally to heating ventilating and air conditioning systems and, more specifically, to a size adjustable filter element being partially fabricated on site wherein one or more rigid wire frames are fastened to one another using a high tensile strength adhesive tape to form a structure substantially conforming to the units original equipment manufacturers filter housing.
The filter media consists of a mixture of natural and synthetic fibers and is bonded to a thin wire mesh backing leaving an amount of filter media on the top and bottom that extends beyond said wire mesh. Said wire mesh provides rigidity, which enables the filter media to be pleated and to keep said formed pleating over the life of the fabricated filter element. Said filter media is attached to the rigid wire frame by selectively drawing a portion of a pleat around each side of a wire member and securing said pleats to each other by means of epoxy coated staples, being rust resistant, thereby securing said filter media to said rigid wire frame.
When the filter media has been attached to the rigid wire frames, having been adjusted to conform to the existing filter element housing, the on-site fabricated filter element comprised of a fabric-like material attached to a rigid wire frame having a skirt of filter media, having no thin wire backing, extending beyond said rigid wire frame on two sides can be slid into the appropriate original equipment manufacturers filter housing wherein the skirt of said on-site fabricated filter will fill and conform to said filter housing.
2. Description of the Prior Art
There are numerous means for removing particle matter from atmospheric air before introducing said air into a heating, venting and/or air conditioning system. Usually these systems have one or more removable and replaceable rigid filter elements which are manufactured to a specific length and height and being inserted into a channeled filter housing to effectively seal the unit from the introduction of dust, dirt, and pollen.
Over time the filter element will be periodically replaced due to the build up of contaminants on the filter media which requires the technician to purchase a filter element from the original equipment manufacturer or some third party supplier whose sole business is manufacturing generic filter elements.
This system leaves the technician with little choice but to stock every conceivable filter element and to carry them around from job site to job site or order the replacement filter element and schedule a second on-site maintenance call to install the element when it arrives.
Additionally, the replaceable rigid filter elements allow significant contaminated, un-cleaned airflow to circulate around the replaceable rigid filter elements due to variations in tolerances of the replaceable rigid filter elements and the original equipment manufacturers' channeled filter housing. This bypass forces the technician to mechanically clean the original equipment manufacturers' air conditioning system and the attached ductwork and air distribution registers much more frequently than necessary if a proper air seal integrity were achievable and is detrimental to the mechanical and thermodynamic efficiency of the original equipment manufacturer's air conditioning system.
Further, the standard practice of employing cardboard superstructure to give rigidity to the prior art replaceable filter element causes the rigidity to deteriorate during high humidity conditions or rainstorms thus producing situations in which the replaceable rigid filter element is drawn out of the original equipment manufacturers' air conditioning system channeled filter housing and into the air moving fan destroying the replaceable rigid filter element's ability to filter at all. The use of this cardboard superstructure also blinds a portion of the replaceable rigid filter element and reduces the capacity of the element to capture and retain particulate matter. Finally, the use of this cardboard superstructure demands the use of wood fiber and is not environmentally conservative.
Not only does this cost the service technician by having to visit the same site twice, and having to perform certain functions twice, and the inconvenience to the client, having to shut the system down again, there is also the case of being unable to find or order the filter cartridge due to the age of the equipment thereby requiring the installation of an almost fits filter cartridge which further stresses an aged system that will require more frequent maintenance visits, requiring more time to remove the inevitable buildup of dirt and debris from within the system that is entering from around the edges of an ill fitting filter cartridge, as well as, lost customers who can't or won't understand why their system performance is so poor and feels that their service bureau is more interested in selling them a new system rather than maintaining the one they have.
Therefore, it is felt that the need exists to provide the technician with the ability to fabricate the needed filter element on-site, on an as-needed basis and in a custom size providing a positive seal, eliminating the reliance on cardboard for rigidity all of which will reduce system maintenance, improve equipment performance, foster good customer relations, and assist in conserving valuable forest resources.